Summer 2011 selection
Explanation/disclaimer: click to expand/contract
These howlers are real students' mistaken answers to Biology questions and explanations of Biological phenomena.
Some show problems with spelling, expressing themselves clearly, comprehension or recall of scientific concepts.
In other words do not take these seriously - they are all wrong in some way.
It is my hope that they first make readers laugh, and then make them think.
Other sections of the BioTopics website are more educational and informative but not so entertaining
- lofty ideals shared with the Ig Nobel prizes and the BBC mission statement.
Parents and offspring may share curtain characteristics
Nitrogen gas from the air is taken up by nitrogen-fixating bacteria
Source of human forensic material: root hair cell
Nitrates are taken up by piano which are eaten by animals (plants mis-spelt)
Because we get 50% of our DNA from each of our parents it is semi predictable
The Calvin cycle occurs in the stoma of a leaf
The Krebs cycle in itself is cyclic
Hormones are specific to one cell - travel into bloodstream and get unloaded at areas that need them
Acetyl choline forms complexes with synaptic messages
All biological processes have an optimum temperature which is usually hotter rather than colder
Stomata open and close allowing water to enter
The lower surface of the leaf is involved in absorption - gas exchange whereas the upper surface functions to do with transpiration - loss of substances
Pear trees are fruit trees and so they are different from other non fruit-growing trees
Evaporated water rises with the warm air
When the pancreas releases LH it inhibits the production of oestrogen
Pre mRNA is MRNA before thymine has changed to uracil.
The nitrates directive has been developed to reduce the amount of affluent and nitrogen that
flows into lakes and rivers
Animals in particular herbivores eat plants for example a cow.
In some countries people are lactose intolerant as the gland that produces the enzyme lactase has been turned off
CO2 enters the leaf via stroma
The 4 carbon compound is turned into a 3 carbon compond by removal of a H+ ion
Fragments at bottom of gel are heavier
Hydrolysis breaks down amino acids by the addition of water
More RNA is being used in translation and so is being cut up by DNA ligase
Explain the change in RNA between 60 and 80% of the time spent as pupa
- It is growing into an adult pupa
- Pupa is ready to lay eggs
Explain how the units [cm3g-1h-1] in the table for oxygen consumption by iguanas at rest allowed scientists to compare oxygen consumption of different iguanas:
- they are based on iguanas volume, mass and height
- they take into account the surface area of the lizards
- smaller numbers are easier to compare
- allows different surface area:body ratio to be used
- mass and length of iguanas could be correlated
- it looks at the cm3 and grams per hour of oxygen consumption
- you can compare iguanas' oxygen consumption per cm3
- measuring per cm3 different iguanas could be compared accurately
- it enables you to determine the mass in cm3 of different iguanas
- it shows iguanas vary in size, weight and height
- mean rate of O2 was measured per cm3 so larger iguanas would not affect the result
- the mean takes into account a wide range of values so they can be compared to the mean as it is an average
- They are not specific units. They are relative to the animal's mass and height so no account of body mass and size is taken
- mean is calculated, so the results can be plotted on a graph
- they could be compared with an active iguana
- allows comparison as a proportion of each cm3
- this includes height/length of an iguana as well as the mass
- it allowed comparisons with iguanas of different volumes
- they are objective and therefore unaffected by any individual difference between the iguanas
- it is very generalised .... could be used on all species of iguanas
- take into account iguanas lung capacity
- these are small units therefore give precise result comparing different oxygen level
- they used mean ox consumption because results came from many iguanas
- it enables the data to be more representative of the iguana population
- as the units have been changed to cm3 this means results are clear and easy to compare
- size won't affect the results because only the rate of uptake per volume is taken
- different iguanas have different body temps
- because body temp and O2 blood concs are proportional
- rate of consumption is measured as volume by mass per hour
- mean gives an average so it can be seen if the rate is faster/slower than average
- because it is measured per unit time you can compare ... different species
- these units are transferable to other iguanas - nothing about the units makes it these iguanas specifically
- they are in grams per hour in cm3, and precise decimals
- they gave a set universal measure that could be used between individuals of the species
- it's in a ratio form so it's easy to compare
- units are in decimals .. instead of whole numbers where difference would be hard to see
- it is measured over a long time, i.e an hour, making results more representative
When an iguana's body temperature is increased, its oxygen consumption increases because:
- more respiration is required to keep its body low
- oxygen is consumed to keep body temp stable
- oxygen is the final exceptor
- respiration allows for an increased amount of oxygen in the body to remove the CO2 inside
- it will lose more oxygen through sweat
Description of electrophoresis method on DNA fragments:
- Put the fragments on some gel, give it an electric shock and then the gel will run to the positive end
- By separating the sequence down to individual amino acids, they can calculate the number of bases
- It separates fragments in the order of the 4 different bases
- It allows you to read the base sequence
- It separates double stranded copy of DNA to single stranded
Explain why the percentage of bases from the middle and the end part of a chromosome are different:
- ends contain information from mother and father and they have crossed over in the middle
- the % of bases will be different as they come from different people
- transcription more often occurs in the middle part
Explain changes in RNA in later stages in the pupa:
- reverse translation of proteins into RNA to form adult fly tissue
- pupa is about to reproduce
Explanation of phototropism:
- IAA causes shaded side to become heavy
- IAA causes plant to move to the light
- IAA allows the plant to grow in the opposite direction
- cells on the shaded side elongate and push the plant towards the sun
- it places the leaves even closer to the sun
Why do farmers sometimes give progesterone to sheep to prevent ovulation?
It fools the sheep's body into thinking it's pregnant